Petteri Teikari

Petteri Teikari

orcid

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 2012 in Journal of Neuroscience Methods
Verified
Journal Article
Closed access
PTPetteri Teikari
Petteri Teikari
Raymond P. NajjarRaymond P. Najjar
Raymond P. Najjar
HMHemi Malkki
Hemi Malkki
KKKenneth Knoblauch
Kenneth Knoblauch
DDDominique Dumortier
Dominique Dumortier
HCHoward M. Cooper
Howard M. Cooper

17 March 2023 in Scientific Data
Verified
Journal Article
Open access
PDF file
CPCharissa Poon
Charissa Poon
PTPetteri Teikari
Petteri Teikari
MRMuhammad Febrian Rachmadi
Muhammad Febrian Rachmadi
HSHenrik Skibbe
Henrik Skibbe
KHKullervo Hynynen
Kullervo Hynynen
We present MiniVess, the first annotated dataset of rodent cerebrovasculature, acquired using two-photon fluorescence microscopy. MiniVess consists of 70 3D image volumes with segmented ground truths. Segmentations were created using traditional image processing operations, a U-Net, and manual proofreading. Code for image preprocessing steps and the U-Net are provided. Supervised machine learning methods have been widely used for automated image processing of biomedical images. While much emphasis has been placed on the development of new network architectures and loss functions, there has been an increased emphasis on the need for publicly available annotated, or segmented, datasets. Annotated datasets are necessary during model training and validation. In particular, datasets that are collected from different labs are necessary to test the generalizability of models. We hope this dataset will be helpful in testing the reliability of machine learning tools for analyzing biomedical images.

1 January 2019 in Therapeutic Advances in Ophthalmology
Verified
Journal Article
Open access
PTPetteri Teikari
Petteri Teikari
Raymond P. NajjarRaymond P. Najjar
Raymond P. Najjar
LSLeopold Schmetterer
Leopold Schmetterer
DMDan Milea
Dan Milea
Deep learning has recently gained high interest in ophthalmology due to its ability to detect clinically significant features for diagnosis and prognosis. Despite these significant advances, little is known about the ability of various deep learning systems to be embedded within ophthalmic imaging devices, allowing automated image acquisition. In this work, we will review the existing and future directions for ‘active acquisition’–embedded deep learning, leading to as high-quality images with little intervention by the human operator. In clinical practice, the improved image quality should translate into more robust deep learning–based clinical diagnostics. Embedded deep learning will be enabled by the constantly improving hardware performance with low cost. We will briefly review possible computation methods in larger clinical systems. Briefly, they can be included in a three-layer framework composed of edge, fog, and cloud layers, the former being performed at a device level. Improved egde-layer performance via ‘active acquisition’ serves as an automatic data curation operator translating to better quality data in electronic health records, as well as on the cloud layer, for improved deep learning–based clinical data mining.

16 September 2023 in Medical Image Analysis
Verified
Journal Article
Open access
MGMark S. Graham
Mark S. Graham
PTPetru-Daniel Tudosiu
Petru-Daniel Tudosiu
PWPaul Wright
Paul Wright
WPWalter Hugo Lopez Pinaya
Walter Hugo Lopez Pinaya
PTPetteri Teikari
Petteri Teikari
MCM. Jorge Cardoso
M. Jorge Cardoso
Any clinically-deployed image-processing pipeline must be robust to the full range of inputs it may be presented with. One popular approach to this challenge is to develop predictive models that can provide a measure of their uncertainty. Another approach is to use generative modelling to quantify the likelihood of inputs. Inputs with a low enough likelihood are deemed to be out-of-distribution and are not presented to the downstream predictive model. In this work, we evaluate several approaches to segmentation with uncertainty for the task of segmenting bleeds in 3D CT of the head. We show that these models can fail catastrophically when operating in the far out-of-distribution domain, often providing predictions that are both highly confident and wrong. We propose to instead perform out-of-distribution detection using the Latent Transformer Model: a VQ-GAN is used to provide a highly compressed latent representation of the input volume, and a transformer is then used to estimate the likelihood of this compressed representation of the input. We demonstrate this approach can identify images that are both far- and near- out-of-distribution, as well as provide spatial maps that highlight the regions considered to be out-of-distribution. Furthermore, we find a strong relationship between an image's likelihood and the quality of a model's segmentation on it, demonstrating that this approach is viable for filtering out unsuitable images.

24 October 2012 in Journal of the Optical Society of America A
Verified
Journal Article
Closed access
PDF file
PTPetteri Teikari
Petteri Teikari
Raymond P. NajjarRaymond P. Najjar
Raymond P. Najjar
KKKenneth Knoblauch
Kenneth Knoblauch
DDDominique Dumortier
Dominique Dumortier
PCPierre-Loïc Cornut
Pierre-Loïc Cornut
Claude GronfierClaude Gronfier
Claude Gronfier
Many physiological and pathological conditions are associated with a change in the crystalline lens transmittance. Estimates of lens opacification, however, generally rely on subjective rather than objective measures in clinical practice. The goal of our study was to develop an improved psychophysical heterochromatic flicker photometry technique combined with existing mathematical models to evaluate the spectral transmittance of the human ocular media noninvasively. Our results show that it is possible to accurately estimate ocular media density in vivo in humans. Potential applications of our approach include basic research and clinical settings on visual and nonimage-forming visual systems.

20 May 2021 in SportRxiv
Verified
Preprint
Open access
PTPetteri Teikari
Petteri Teikari
APAleksandra Pietrusz
Aleksandra Pietrusz
In strength training, personalised strength training (autoregulation) approaches have been used to individualise exercise programs with monitoring for dynamic adjustment based on the individual response to training. While this transition from tradition-based training to evidence-based training framework has been an improvement in training practices, we argue that the future of strength training will also incorporate deep learning models powered by data. We refer to this data-driven framework as precision strength training inspired by the similar modeling frameworks used in precision medicine. In contrast to current personalised training in which the acquired athlete data is often subject to human expert decision-making, we are anticipating the rise of human-in-the-loop systems with an augmented coach who will be doing decisions collaboratively with the machine. Similar to other precision frameworks, such as precision health, we envision such a future to take decades to be realised and we focus here on practical short-term targets on a way to long-term realisation. In this chapter, we will review the measurement technology needed for continuous data acquisition from an individual during training/physical activity, how to acquire these datasets for the development of such systems and, how a proof-of-concept system could be developed for powerlifting training with applicability to general strength and conditioning (S&C) and physical rehabilitation purposes. Additionally, we will evaluate how the user experience (UX) of the system feedback and visualisation could be designed.